RU210585U1 - JET MILL FOR ULTRA FINE GRINDING - Google Patents

Abstract

The utility model relates to devices for ultrafine grinding of various materials and can be used in the paint and varnish industry, in the production of building materials and ceramics, as well as in other industries. The utility model is aimed at increasing the dispersion of the finished product by creating an additional vortex flow and increasing the degree of separation for due to the installation of a classifying impeller inside the grinding chamber. This is achieved by the fact that the jet mill contains a grinding chamber 1 with a loading pipe 2 and an unloading pipe 4. In the loading pipe 2 there is a nozzle 5 for supplying the energy carrier. A baffle 6 is installed in the lower part of the grinding chamber 1. Additional nozzles 7 are tangentially installed in the central part of the grinding chamber 1 for supplying the energy carrier. Additional nozzles 7 for supplying the energy carrier are located diametrically opposite to each other. The chipper 7 is made of a conical shape. In the proposed solution, the loading pipe 2 is installed with the possibility of rotation and is provided in the lower part, located in the grinding chamber 1, rigidly fixed along its outer surface, with a classifying impeller 3 having the shape of a truncated cone, the smaller base of which is oriented inside the grinding chamber 1. Fig. 2.

Description

The utility model relates to devices for ultra-fine grinding of various materials and can be used in the paint and varnish industry, in the production of building materials and ceramics, as well as in other industries.

Known design of a vertical jet mill [USSR author's certificate for the invention No. 957961, IPC - B02C 19/06 Appl. 01/04/1980; publ. 09/15/1982, bul. No. 34]. The vertical jet mill contains an accelerating pipe installed in the grinding chamber, a breaking plate, a feed material input chute and a separation chamber.

The disadvantage of this mill is the low dispersion of the finished product.

Known design jet mill [USSR author's certificate for the invention No. 961772, IPC - 2000.01 B02C 19/06 Jet mill; dec. 10/19/1979; publ. September 30, 1982]. The jet mill contains a fixed chamber (grinding chamber), in the central part made in the form of a horizontally located pipe, having a spherical surface at the ends, loading and unloading nozzles, an impact plate (impact plate) located coaxially with the vertical axis of the chamber, nozzles located on the inner surface inlet pipe and under the impact plate, a hollow reflector mounted coaxially to the inlet pipe, which is installed coaxially with the impact plate.

The disadvantage of this mill is the low dispersion of the finished product, due to the lack of a classifying device.

The closest to the proposed design is a jet mill [RF author's certificate for the invention No. 190985, IPC - 2006.01 B02C 18/06 Jet mill; dec. 05/22/2019; publ. May 22, 2019]. The jet mill for ultra-fine grinding contains a grinding chamber with inlet and outlet nozzles. On the inner surface of the loading pipe there is a nozzle for supplying the energy carrier. A baffle is installed at the bottom of the grinding chamber. In the central part of the grinding chamber there are tangentially installed additional nozzles for supplying the energy carrier. Additional nozzles for supplying the energy carrier are located diametrically opposite to each other. The chipper is made of a conical shape. Guiding elements oriented towards the energy carrier supply are fixed on the chipper.

The following set of prototype features coincides with the essential features of the claimed utility model: a grinding chamber with loading and unloading nozzles, a nozzle for supplying an energy carrier, and a baffle is installed in the lower part of the grinding chamber. In the central part of the grinding chamber there are tangentially installed additional nozzles for supplying the energy carrier.

The disadvantage of the prototype is the low dispersion of the finished product, due to the lack of a classifying device.

The utility model is aimed at increasing the dispersion of the finished product by creating an additional vortex flow and increasing the degree of separation by installing a classifying impeller inside the grinding chamber.

This is achieved by the fact that the jet mill contains a grinding chamber with loading and unloading nozzles. In the loading pipe there is a nozzle for supplying the energy carrier. A baffle is installed at the bottom of the grinding chamber. In the central part of the grinding chamber, additional nozzles are tangentially installed for supplying the energy carrier. Additional nozzles for supplying the energy carrier are located diametrically opposite to each other. The chipper is made of a conical shape. In the proposed solution, the loading pipe is installed with the possibility of rotation and is provided in the lower part, located in the grinding chamber, rigidly fixed along its outer surface, with a classifying impeller having the shape of a truncated cone, the smaller base of which is oriented inside the grinding chamber.

This design of the jet mill will increase the dispersion of the finished product by installing a classifying impeller in the grinding chamber, which, rotating at high speeds, will exclude the release of coarse fraction from the grinding chamber, in addition, with this mode of rotation of the classifying impeller, an additional vortex flow will be created, which will increase the pressure the force acting on the particles of the material for effective abrasion.

The essence of the utility model is illustrated by graphic material, where in Fig. 1 shows a sectional view of an ultrafine jet mill, FIG. 2 shows view A of FIG. 1.

The jet mill consists of a grinding chamber 1, in the upper part of which, coaxially with the vertical axis, there is a loading pipe 2 with a classifying impeller 3, which has the shape of a truncated cone, the smaller base of which is oriented inside the grinding chamber 1. The classifying impeller 3 is fixed, for example, by welding, on the loading nozzle 2. The rotating loading nozzle 2 is mounted on bearings, and due to the rigid connection with the classifying impeller, it transmits torque to it. The diameter of the discharge pipe 4 is larger than the diameter of the boot pipe 2. A nozzle 5 is installed above the boot pipe 2 for supplying an energy carrier, for example, compressed air. In the lower part of the grinding chamber 1, coaxially with the loading pipe 2, there is a baffle 6 made of a conical shape, the smaller base of which is oriented inside the grinding chamber 1. In the central part of the grinding chamber 1, additional nozzles 7 are tangentially installed for supplying an energy carrier, for example, compressed air, located diametrically opposite to each other.

Jet mill for ultrafine grinding works as follows.

The material to be crushed, for example, red lead, enters the loading pipe 2, which rotates around its axis. The material is accelerated by jets of air coming out of the nozzle 5 for supplying energy and enters the grinding chamber 1. Part of the material enters the conical bump 6, and the other part, due to the centrifugal force that arises from the rotation of the loading pipe 2, is carried away to the walls of the grinding chamber 1. In the grinding chamber 1, the material is crushed against the bumper 6 and is twisted in the direction of movement of the energy carrier (compressed air) supplied from the tangentially installed additional nozzles 7. Under the action of centrifugal force, the particles are pressed against the inner surface of the grinding chamber 1 and are crushed due to abrasion of the material about the wall of the grinding chamber 1. When the particle has been crushed, the aerodynamic resistance force acting on it has become greater than the centrifugal force, then the material particle moves to the discharge nozzle 4. The rotation of the classifying impeller 3 at high speed (700-1500 rpm) eliminates the output of the coarse fraction from grinding chamber 1. In addition, when The rotation of the classifying impeller 3 will create an additional vortex flow, which increases the clamping force acting on each particle. Due to repeated abrasive action, the desired particle size is achieved, and the finely ground material passes through the classifying impeller 3 into the discharge pipe 4.

The use of this design of the utility model due to the classifying impeller will increase the dispersion of the finished product.

Claims (1)

A jet mill for ultra-fine grinding, containing a grinding chamber with loading and unloading nozzles, a nozzle for supplying energy carrier is located in the loading nozzle, a baffle is installed in the lower part of the grinding chamber, and additional nozzles for supplying energy carrier are tangentially installed in the central part of the grinding chamber, located diametrically opposite relative to each other, characterized in that the loading pipe is installed with the possibility of rotation and is provided in the lower part, located in the grinding chamber, rigidly fixed along its outer surface, with a classifying impeller having the shape of a truncated cone, the smaller base of which is oriented inside the grinding chamber.

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